Electric clock.



No. 7|l,944. Patentad 0ct. 28, |902.

' C. H. EBOOK.

ELECTRIC CLOCK.

Anne-.cion ma sepa. ao, 1901.)

(lo Model.)

UNITED STATES PATENT OFFICE.

CHARLES M. CROOK, OF BRISTOL, CONNECTICUT, ASSIGNOR, BY MESNEASSIGNMENTS, TO NATIONAL SELF-VINDING CLOCK COMPANY, OF JERSEY CITY, NEWJERSEY, AND BRISTOL, CONNECTICUT, A COR- PORATION OE NEV JERSEY.

ELECTRIC CLOCK.

SPECIFICATION forming part of Letters Patent No. 711,944, dated October28, 1902.

Application filed September 30, 1901. Serial No. 77,005. (No model.)

To (all whom it may concern.'

Be it known that I, CHARLES M. CRooK, a citizen of the United States ofAmerica, and a resident of Bristol, Connecticut, have invented certainnew and useful Improvements in Synchronizing-Clocks, of which thefollowing is a specification, reference being had to the accompanyingdrawings, forming a part thereof.

The purpose of this invention is to provide an improved synchronizingrdevice and to overcome certain diiiiculties which are encountered insynchroniziiig-clocks, in which the staffs of the several hands to beset are driven in a train by which they are positively connected-thatis, not yieldingly connected-so that one synchronizing action sets allthe hands. It will be apparent that if the hands are not rigid withtheir respective staffs they are liable at the synchronizing action tobe carried by the momentum of that action past the points, respectively,to which they are positively carried by the rotation of their staffs,slipping at the frictional connection with said staffs, and it will beapparent, on the other hand, that if they are rigidly and positivelyconnected with their staffs all the Wheels of the train comprising andconnecting said stals and the shaft or gear which is primarily actedupon in the synchronizing laction sustain a necessary relation whichcannot be altered without defeating the proper setting of the hands-thatis, the several wheels of the train must be so meshed thatthe handsshall each and all be brought to proper position on their respectivedials by the rotation of the wheel or stati", which is primarily actedand rotated to a certain invariable position by the synchronizingstroke; but if the hands are rigidly and unchangeably attached to theirstas, respectively, then whenever the clock is taken apart for repairsor cleaning it must be reassembled with the wheels respectively meshingat the same cogs as when irst assembled-that is, there will be only oneproper mesh-and any change in that respect will throw one or another ofthe hands into inconsistent position. This would necessitate markingeach wheel to denote the proper teeth to be lneshed, and any disregardfor such marking would cause the hands to come to disagreeing positionswhen the synchonizing stroke is made. the matter of ordinary repairs andcleaning expensive and would practically necessitate for thatotherwise-simple work the employment of an expert familiar with theparticular clock-movement.

This invention consists in the improved synchronizing device set out inthe claims and in the device also set out therein 'for overcoming theabove-mentioned difficulty by making it possible to assemble the ltrainin any manner that is, causing the wheels to mesh as they may chance-andyet bring the hands to agreed positions.

In the drawings, Figure 1 is a front elevation of a portion of aclock-movement embodying my improvements, the frame and part of thetrain being cut away to disclose the more essential parts of thestructure. Fig. 2 is a section at the line 2 2 on Fig. l. Fig. 3 is adetail elevation, partly sectional, of the synchronizing device, sectionbeing made at the line 3 3 on the Fig. 2. Fig. 4 is a detail sectionaxial with respect to the minute-hand staff, showing hand securing andadjusting means. Fig. 5 is a detail section at the line 5 5 on Fig. 4.Fig. G is a detail section at the line 6 (3 on Fig. 4f. Fig. 7 is adetail section axial with respect to the seconds-hand staff and pinion,showing connection of said shaft with the escape-wheel shaft and themeans of adjustment. Fig. Sis a section at the line 8 S on Fig. 6. Fig.9 is a detail section in the plane of the axis of the shaft operatedupon for synchronizing, cutting through the stud or crank-wrist on whichthe synchronizing-lever acts and adjacent parts.

A is the front plate, and A the rear plate, of the frame.

B is the prime wheel of the train, I) being the main shaft, on whichsaid wheel is rigid, said main shaft being also the minute-hand stall.The motor connections are not shown, not being a part of this invention.The escape-wheel shaft (seen at d) is in line with and at its forwardend obtains bearingin the rear end of the seconds-hand staff d', andthere is one shaft only, c, intermediate the This would make IOO mainshaft b and the seconds-hand stad d', and the train from the prime wheelto the seconds-hand staff comprises the pinion C on the intermediateshaft c, the gearvC, rigidly connected with said pinion by thecrank-wrist or eccentric post c2, on which is the antifric!` tion-rollC2, and the seconds-hand pinion D,

rigid with the staff d', which projects through the front plate and isconsiderably extended to afford means for mounting thereon theseconds-hand D. To the escape-wheel stai` there is an independent train,commencing with a wheel c3, loose on the shaftcand driven by frictionfrom the back of the pinion C', as indicated by the tripod4spring c3.This is in accordance with my Patent No. 610,229, dated September 6,1898, and the construction in this respect need not be furtherdescribed. The shaft l) penetrates the front plate A and just forwardthereof is reduced yand'squared at b and receives on said squaredportion the cupped disk E, which has a square aperture to tit the shaftatthat point, and on the stad b,forward of the cupped disk E,there islodged a sleeve G, which is squared at the forward end to receive theminute-hand. This sleeve has at the rear end the disk G, adapted toenter the cupped disk E, the former being interiorly and the latterexteriorly very slightly tapered to permit the -one to enter the otherand obtain by slight pressure firm frictional engagement for the work tobe done, equivalent to a positive attachment of the two parts to eachother. positive connection more certainly positive, the periphery ofthedisk G and the inner wall of theilange of the cupped disk E are finelycorrugated or serrated, so that when the disk is entered into the cupthe engagement is perfectly positive and rigid. The number ofcorrugations or serrations is equal to oran exact multiple of the numberof teeth on'the gear-wheel B, so that the hands can be set in correctposition whatever teeth of said wheelI is meshed with the pinion C atthe synchronizing position of said pinion. The forward end ot' sta b isthreaded, and a thumb-nut G2 thereon operates to force the sleeve G backon the staff and sink the disk G' in the cupped disk E, thus forcing andretaining the two parts of the clutch which these two disks constitutein engagement. I do not limit myself to the serrations described as themeans of engagement between the two parts of the clutch, since obviouslythis expedient is only superior for certainty and rigidity of engagementto that which would be eiected by mere friction between the twoslightly-tapered elements; but if such serrations are employed it isimportant that their number should be as describedto wit, equal to or amultiple of the number of the teeth on the gear-wheel which carries thestad, so that there shall be as many dierent positions possible in therelative adjustment of the two clutch elements as would be possible byTo render this substantially shifting the mesh of said stai-carryingwheel with the next preceding pinion.

The first wheel K of the train connecting the minute and hour hands isrigid with the sleeve G at the rear portion of said sleeve immediatelyforward of the clutch-disk G', so thatthe hour-hand is set with theminutehand, the proper relation of the two hands being preserved as isusual. in any setting action. The diameter of the disk G is sufficientto cause the disk to lap behind the intermeshing teeth of the gear KandA next Wheel K of the 'hands-train. This prevents any danger ofthrowing the gear K out of mesh with the gear K' when the sleeveis movedforward to release the clutch. This construction has a value independentof the synchronizing or automatic setting of the hands by asynchronizingr device, for it dispenses :with the necessity for thecustomary means of permitting the hands to be set at willthat is, thefrictional connection between the minute-hand sta and the remainder ofthe motor-train, for with the construction above -described while thehands are at al1 times positively driven, yet by slacking the nut anddrawing forward lthe minute-hand and its sleeveto disengage the twoparts of the clutch the entire hands-train commencing with the wheel Kon the sleeve G is freed from the anterior driving-train and the handsmay be set at will, preserving their proper relations through the trainwhich connects them, and then byypushing back the hand and its sleeveand applying the thumb-nut the clutch again operates to hold the handsas set with respect to the remainder of the train.

L is the synchronizing-electromagnet. L is its armature carried on thelever M, which extends across the shaft c above the path or orbit of thecrank-wrist c2, so that when the magnet is energized the armature leverstrikes across the axis of the said shaft in the plane of the orbit ofthe wrist and encounters the latter wherever it stands, and if it is outof its proper positionthat is, the position it would occupy if the clockwas running accurately and indicating the exact time at thesynchronizing instant, said position being the lowest position in itsorbit-'it will be forced to that position unless it is almostdiametrically opposite the same. The practical range of adjustment whichmay be caused by the stroke of the lever upon the vwrist is aboutthirty-six degrees less than onehalf revolution, and, since in thetrain, as shown in drawings, one revolution of the shaft c occupiesseven and one-half .minutes one-half revolution less thirty-six degreescorresponds to three minutes, so that correction can bemadeof an erroramounting to three minutes, either slow or fast.

When synchronizing action is performed upon a shaft intermediate theminute and and seconds hand staffs, as in the construc- IOO IIO

being set at the Zero-point of their respective tion illustrated, inorder that both hands may be rigidly secured to their staffs,respectively, the saine or equivalent provision should be made foradjusting the secondshand on its staff as that above described withrespect to the minute-hand. This is not so essential, however, as inrespect to the minute-hand, because the carrying-wheel of its staffbeing a pinion with only twelveteeth it is not a diicult matter to takenote of the position of the hand when assembling the train or toreadjust t-he meshes of this pinion with the next preceding wheel.However, for the purpose of rendering the secondshand adjustable withthe same effect as above described I provide it with a two-part clutchdevice. The seconds-hand has its sleeve, which is split to adapt it tohold strongly by friction on its staff, expanded at the rear end to4increase its periphery and provided at such increased periphery withtwelve notches to correspond with the twelve teeth of itscarrying-pinion, and through the staff (Z/ a little forward of the frontplate I set a transverse pin (Zw, which is adapted to engage any twonotches on sleeve. The frictional grasp of the split sleeve on the pinis suiicient to prevent its longitudinal displacelnent by accident, andso long as there is no longitudinal displacement the pin lodged in thenotches effects a secure positive engagement of the hand with the staffafter the movement is fully assembled, the synch ronizing stroke beinggiven and both hands then dials.

Iclainr- 1. In a clock a gear-frame and train therein connectingpositively the minute and seconds hand staffs; synchronizingmeansoperating on the shaft of the train to set both hands at oneoperation, said hands being rigidly secured to their respective shafts;the means of securing one of the hands consisting of a two-part clutch,having one part rigid with the hand, and the counterpart rigid with thestaff, said part and counterpart beingadapted to be disengageablyengaged positively-gas distinguished from yieldingly, against relativerotation at as manydifferent relative positions as there are teeth onthe gear-wheel which carries said staff, and means accessible i foroperation outside the frame for effecting i such engagement anddisengagement at will. i

2. In aclock, a gear-frame and train therein, a hand-staff, which saidtrain drives positively; a synchronizing-lever and a shaft in said trainon which said lever acts to rotate it to certain position; a handadapted to be i rigid with the hand-staff, and means for disengageablysecuring the hand to the staff, comprising atwo-part clutch, whose partsare adapted to be engaged positively, as distinguished from yieldingly,at as many relative positions as there are teeth on the gear-wheel whichcarries said staff, means connected with i one of said parts accessibleoutside the frame for effecting the engagement and disengagement of saidclutch parts.

3. In a clock, a gear-train, two hand-staffs which said train drivespositively, a synchronizing-lever and a shaft in the train int-ermediatesaid hand-staffs on which said lever acts to rotate it to a certainposition, the hands being adapted to be rigid with their staffsrespectively, .the means for making them rigid being a two-part clutch,one part being rigid with the hand and the other with the staff, anddisengageably engageable positively, as distinguished from yieldingly,at as many different positions as there are teeth on the staff-carryingwheel.

4. In a clock-train, the minute-hand staff, the minute-hand, a two-partclutch device for making the hand rigid with the staff, one part of theclutch being rigid with the staif, the other part having a sleeve bywhich it is mounted loose on the staff, and which at the forward endcarries the hand rigidly, the staff projecting from the forward end ofthe sleeve and means for positively forcing and holding the sleeve backto effect unyielding engagement of the clutch and the hands-train havingits first wheel rigid with saidy sleeve forward of the clutch-disk.

5. In a clock, a gear-frame and train therein connecting positively theminute and seconds hands staffs; synchronizing means operating on ashaft of the train to set both hands at one operation, said hands beingsecured rigidly to their respective staffs, the means for securing oneof the hands being a two-part clutch consisting of a cupped disk rigidwith one of said elements and a slightly-tapered disk rigid with theother element and adapted to enter the cupped disk, the part rigid withthe hand being movable on the hand-staff to become engaged w-ith andreleased from the other part; and means accessible outside the frame formoving said movable part into engagement with the other part of theclutch and for holding' it unyieldingly in such engagement.

6. In a clock, a gear-frame and train therein; a hand-staff which saidtrain drives positively; a synchronizing-lever, and a shaft in saidtrain on which said lever acts to rotate it to a certain position; ahand adapted to be rigid with the hand-staff; and means fordisengageably securing said hand and staff together consisting of atwo-part clutch composed of a cupped disk rigid with one of saidelements, and a slightly-tapered disk rigid with the other elementadapted to enter the cupped disk, the part rigid with the hand beingmovable on the hands-stall to become engaged with and released from theother part; and means accessible outside the frame for moving saidmovable part into engagement with the other part of the clutch and forholding it unyieldingly in such engagement.

IOO

IIO

IIS

said train drives positively; a synchronizinglever, and a'shaft in saidtrain on which said lever acts to rotate it to a certain position; ahand adapted to be rigid with the hand-staff; and means fordisengageably securing such hand to the staff consisting of a two-partclutch comprising a cupped disk rigid with one of said elements and aslightly-tapered disk rigid with the other element adapted to enter thecupped disk, the part rigid with the hand being movable on thehand-staff to become engaged with and released from the other part; anda nut on the forward end of the hand-staff for forcing the two parts ofthe clutch into engagement.

8. In a clock, a gear-train, and a hand-stad which said train drivespositively; a synch ronizing-le ver, and a shaft in said train on whichsaid lever acts to rotate it to a certain position; a hand adapted to berigid with the handsiaif; means fordisengageablysecuring such hand tothe staff consisting of a two-part clutch comprising a cupped disk rigidwith one of said elements and a slightly-tapered disk rigid with theother element adapted to enter the cupped disk, the part rigid with thehand being movable on the hand-stad to become engaged with and releasedfrom the other part, the periphery of the other disk and the innersurface of the cupped disk being corrugated or serrated, the number ofcorru-4 gations or serrations corresponding to the number of teeth onthe stad-carrying gear; and means for positively forcingsaid serrated orcorrugated disks into unyielding engagem'ent.

9. A clock-train having one of its shafts cranked betweenits bearings;an electromagnetpon the clock-frame and its armature, a lever on whichsaid armature is carried, extending across the cranked shaft in theplane of the orbitof the crank-wrist, whereby when the magnet isenergized said lever may drive the crank-wrist to a point of its orbitmost remote in the direction of the movement of thev lever.

10. In a clock-train in connection with the minute-hand staff and theseconds-hand staff, a gear-train positively connecting said staffs, andfrictionally connected with the remainder of the train; a shaft in saidtrain intermediate said hand-staffs, having thedriving and driven wheelson it connected as by acrankwrist or post eccentric to the shaft; theshaft being interrupted at the plane of the orbit ofy such eccentricpost or wrist; va synchronizing electric magnet and its armature, and alever operated bythe armatu re extending across the axis of the shaftand having a range of movement caused by the armature from one 'side tothe other of said axis at the plane of the orbit of the wrist.

ll. In a clock-train in combination with a minute-hand staff and aseconds-hand stai and gear train positively connecting said staifs andfrictionally connected with the remainder of the train, a shaft in saidtrain intermediate said hand-stais having rigid with it between itsbearings an eccentrically-located abutment, or crank-pin, asynchronizing-lever extending across the shaft in the plane of the orbitof the abutment, and means for operating said synchronizing lever tocause it to encounter said abutment and carry its face which makes saidencounter past the axis of the shaft.

l2. In a clock-train in combination with a minute-hand staff and aseconds-hand staff and gear train positively connecting said stads andfrictionally connected with the remainder of the train, a shaft in saidtrain intermediate-said hand-stads having the driving and driven wheelson it connected by a crank-wrist, or post eccentric to the shaft, theshaft being interrupted at the plane ofthe orbit of such eccentric postor wrist, a synchronizing-lever extending across the axis of the shaftand having a range of movement from one side to the other of said axisat the plane ofthe orbit of the Wrist, and means for operating saidlever.

In testimony whereof I have hereunto set my hand, in the presence of twowitnesses, at Chicago, Illinois, this 14th day of September, 1901.

CHARLES M. oRooK.

Witnesses:

WILLIAM J. MALoNE, ALICE E. BROWN.

